[FFmpeg-trac] #7784(undetermined:new): ffmpeg/lavf changes the case of metadata keys
FFmpeg
trac at avcodec.org
Sun Mar 10 20:27:47 EET 2019
#7784: ffmpeg/lavf changes the case of metadata keys
-------------------------------------+-------------------------------------
Reporter: Cigaes | Owner:
Type: defect | Status: new
Priority: minor | Component:
Version: git- | undetermined
master | Keywords:
Blocked By: | Blocking:
Reproduced by developer: 0 | Analyzed by developer: 0
-------------------------------------+-------------------------------------
Start with an Ogg Vorbis file with the reference tags:
{{{
head -c $[44100*4*60] /dev/zero > silence.pcm
oggenc -r -B 16 -C 2 -R 44100 -a Artist -t Title -l Album -c
custom=Comment silence.pcm
}}}
Then use ffmpeg to remux the file:
{{{
./ffmpeg_g -i /tmp/silence.ogg -y -c copy /tmp/silence_ff.ogg
}}}
Check the output:
{{{
$ vorbiscomment silence.ogg
custom=Comment
title=Title
artist=Artist
album=Album
$ vorbiscomment silence_ff.ogg
CUSTOM=Comment
TITLE=Title
ARTIST=Artist
ALBUM=Album
encoder=Lavf58.26.101
}}}
The spec https://xiph.org/vorbis/doc/v-comment.html states that the keys
are case-insensitive, but ffmpeg should nonetheless try to match the
workings of the reference implementation, and/or not change things without
a good reason.
Output of the ffmpeg command-line (does not contain any useful
information):
{{{
ffmpeg version N-93308-g1144d5c96d Copyright (c) 2000-2019 the FFmpeg
developers
built with gcc 8 (Debian 8.3.0-2)
configuration: --enable-shared --disable-static --enable-gpl --enable-
libx264 --enable-libopus --enable-libass --enable-libfreetype --enable-
opengl --assert-level=2
libavutil 56. 26.100 / 56. 26.100
libavcodec 58. 47.103 / 58. 47.103
libavformat 58. 26.101 / 58. 26.101
libavdevice 58. 6.101 / 58. 6.101
libavfilter 7. 48.100 / 7. 48.100
libswscale 5. 4.100 / 5. 4.100
libswresample 3. 4.100 / 3. 4.100
libpostproc 55. 4.100 / 55. 4.100
Input #0, ogg, from '/tmp/silence.ogg':
Duration: 00:01:00.00, start: 0.000000, bitrate: 1 kb/s
Stream #0:0: Audio: vorbis, 44100 Hz, stereo, fltp, 112 kb/s
Metadata:
CUSTOM : Comment
TITLE : Title
ARTIST : Artist
ALBUM : Album
Output #0, ogg, to '/tmp/silence_ff.ogg':
Metadata:
encoder : Lavf58.26.101
Stream #0:0: Audio: vorbis, 44100 Hz, stereo, fltp, 112 kb/s
Metadata:
CUSTOM : Comment
TITLE : Title
ARTIST : Artist
ALBUM : Album
encoder : Lavf58.26.101
Stream mapping:
Stream #0:0 -> #0:0 (copy)
Press [q] to stop, [?] for help
size= 11kB time=00:00:59.99 bitrate= 1.4kbits/s speed=5.97e+03x
video:0kB audio:3kB subtitle:0kB other streams:0kB global headers:4kB
muxing overhead: 318.329468%
}}}
--
Ticket URL: <https://trac.ffmpeg.org/ticket/7784>
FFmpeg <https://ffmpeg.org>
FFmpeg issue tracker
More information about the FFmpeg-trac
mailing list